Ａｌ‐Ｌｉ系合金の鋳造性

Abstract

The casting characteristics of various Al-Li alloys were investigated. Li losses in Al-3%Si-1%Mg-0.15%Zr containing 1, 2 and 3%Li are about 0.1, 0.2 and 0.4%, respectively when the alloys were melted and held for 3ks at 973K in air. The hydrogen content of molten Al-Li alloys is lowered from 1.00ml/100g to 0.75ml/100g when the Ar degassing time is extended from 300s to 1.8ks at 973-983K. The phenol resin-bonded sand mold coated with MgO, heated and then cooled in vacuum is suitable for casting of Al-Li alloys. The fluidity of Al-2%Cu-1%Mg-0.15%Zr and Al-3% Si-1%Mg-0.15%Zr alloys is not almost changed by the addition of Li up to 3%. The fluid length of these Al-Li alloys is inferior around 85% to that of AC4C (Al-7%Si-0.3%Mg).